将build.sb与project/Build.scala和聚合混合使用

Question

在我有这样的事情(简化)之前,使用sbt 0.11.3:

// project/Build.scala
import sbt._
import Keys._

object MyBuild extends Build {
   lazy val standardSettings = Defaults.defaultSettings ++ Seq(
      version      := "0.2",
      scalaVersion := "2.9.2"
   )

   lazy val main = Project(
      id        = "main",
      base      = file( "." ),
      settings  = standardSettings,
      aggregate = Seq( sub )
   )

   lazy val sub = Project(
      id        = "main-sub",
      base      = file( "sub" ),
      settings  = standardSettings
   )
}

但是我想在普通build.sbt文件中保留尽可能多的信息.所以现在我有

// build.sbt
version      := "0.2"

scalaVersion := "2.9.2"

和

// project/Build.scala
import sbt._
import Keys._

object MyBuild extends Build {
   lazy val main = Project(
      id        = "main",
      base      = file( "." ),
      aggregate = Seq( sub )
   )

   lazy val sub = Project(
      id        = "main-sub",
      base      = file( "sub" )
   )
}

但这似乎并没有在我的设置中混合build.sbt到子项目中:

> show version
[info] main-sub/*:version
[info]  0.1-SNAPSHOT
[info] main/*:version
[info]  0.2
> show scala-version
[info] main-sub/*:scala-version
[info]  2.9.1
[info] main/*:scala-version
[info]  2.9.2

如何解决这个问题？我还尝试向settings子项目添加显式,例如

• settings = Defaults.defaultSettings
• settings = Project.defaultSettings
• settings = MyBuild.settings
• settings = main.settings (确定这个应该做什么？!)

......但没有一个有效.

Answer 1

这些信息在sbt的Multi Projects文档的最后一部分中有点隐藏:

当有一个.scala文件设置不同的项目时,很容易在不同的项目中使用重用设置.但即使使用不同的build.sbt文件,通过使用ThisBuild范围来全局应用设置,仍然可以轻松地在主构建中的所有项目之间共享设置.

从而:

// build.sbt
version in ThisBuild := "0.2"

scalaVersion in ThisBuild := "2.9.2"

哇,如果你有二十几把钥匙,这会很糟糕.